Abstract: A system for verifying write data includes a host computer, a controller having a write data path network and a read data path network, and a disk drive array for storing write data. The host computer provides host cyclic redundancy check characters that are appended to blocks of input write data. The write data blocks are divided into subblocks that are processed through separate channels and ports. Port cyclic redundant check characters are appended to each data subblock, including a parity subblock. The read data path network is coupled to receive the data subblocks with the appended host and port cyclic redundancy check characters from the write data path network means and has error detection circuitry for verifying the write data during the write mode.